For the 10^6 time: GM foods is *not* polarizing issue in the U.S., plus an initial note on Pew's latest analysis of its "public-vs.-scientists" survey
Thursday, July 2, 2015 at 10:51AM
Dan Kahan

Keith Kloor asked me whether a set of interesting reflections by Mark Lynas on social and cultural groundings of conflict over GM food risks in Europe generalize to the U.S.

The answer, in my view, is: no.

In Europe, GM food risks is a matter of bitter public controversy, of the sort that splinters people of opposing cultural outlooks (Finucane 2002).

But as scholars of risk perception are fully aware (Finucane & Holup 2005), that ain't so in the U.S.

Consider:

These data come from the study reported in Climate-Science Communication and the Measurement Problem, Advances in Pol. Psych. (2015).

But there are tons more where this came from.  And billions of additional blog posts in which I've addressed this question! Including:

I'm pretttttttttty sure, in fact, that Keith was "setting me up," "throwing me a softball," "yanking my chain" etc-- he knows all of this stuff inside & out.

One of the things he knows is that general population surveys of GM food risks in the US are not valid

Ordinary Americans don't have any opinions on GM foods; they just eat them in humongous quantities.

Accordingly, if one surveys them on whether they are "afraid" of "genetically modified X" -- something they are likely chomping on as they are being interviewed but in fact don't even realize exists-- one ends up not with a sample of real public opinion but with the results of a weird experiment in which ordinary Americans are abducted by pollsters and probed w/ weird survey items being inserted into places other than where their genuine risk perceptions reside.

Pollsters who don't acknowledge this limitation on public opinion surveys -- that surveys presuppose that there is a public attitude to be measured & generate garbage otherwise (Bishop 2005) -- are to legitimate public opinion researchers what tabloid rreporters are to real science journalists.

A while back, I criticized Pew, which is not a tabloid pollster operation, for resorting to tabloid-like marketing of its own research findings after it made a big deal out of the "discrepancy" between "public" and "scientist" (i.e., AAAS member) perceptions of GM food risks.

So now I'm happy to note that Pew is doing its part to try to disabuse people of the persistent miconception that there is meaningful public conflict over GM foods in the U.S.

It issued a supplementary analysis of its public-vs.-AAAS-member survey, in which it examined how the public's responses related to individual characteristics of various sorts:

As this graphic shows, neither "political ideology" nor "religion" -- two characteristics that Lynas identifies as important for explaining conflict over GM foods in Europe-- are meaningfully related to variance in perceptions of GM food risks in the U.S.

Pew treats "education or science knowledge" as having a "strong effect." 

I'm curious about this.

I know from my own analyses of GM food risks that even when one throws every conceivable individual predictor at them, only the tiniest amount of variance is explained.

In other words, variation is mainly noise.

click for regression analysis of gm food risk perceptions... yum!One can see from my own data above that science comprehension, as measured by the "ordinary science intelligence test," reduces risk perceptions (for both right-leaning and left-leaning respondents).

But the pct of variance explained (R^2) is less than 2% of the total variance in the sample. It's a "statistically significant" effect but for sure I wouldn't characterize it as "strong"!

I looked at Pew's own account of how it determined its characterizations of effects as "strong" & have to admit I couldn't understand it.

But with its characteristic commitment to helping curious and reflective people learn, Pew indicates that it will furnish more information on these analyses on request.

So I'll make a request, & figure out what they did.  Wouldn't be surprised if they figured out something I don't know!

Stay tuned...

Refs

Bishop, G.F. The illusion of public opinion : fact and artifact in American public opinion polls (Rowman & Littlefield, Lanham, MD, 2005).

Finucane, M.L. Mad cows, mad corn and mad communities: the role of socio-cultural factors in the perceived risk of genetically-modified food. P Nutr Soc 61, 31-37 (2002). 

Finucane, M.L. & Holup, J.L. Psychosocial and cultural factors affecting the perceived risk of genetically modified food: an overview of the literature. Soc Sci Med 60, 1603-1612 (2005).

 

Article originally appeared on cultural cognition project (http://www.culturalcognition.net/).
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